Broach sharpening machine



Augi 25, 1953 B. wELTE 2,649,662

v BROACH SHARPENING- MACHINE Filed Nov. 5, 1949 Sheets-Sheet 1 f fle. f.

INVEN TOR.

Aug. 25, 1953 B. WELTE 2,649,662

BROACH SHARPENING MACHIN Fi-led Nov. 5. 1949 7 Sheets-Sheet 2 Aug. 25, 1953 B. WEL-rs BROACH SHARPENING MACHINE 7 Sheets-Sheet 5 IN VEN TOR.

Filed NOV. 5, 1949 Aug. 25, 1953 B. WELTE 2,649,662

BROAOH SHARPENING MACHINE JNVENToR.

Allg 25, 1953 B. WELTE 2,649,661..

BROACH SHAHPENING MACHINE Filed Nov. 5.1948 l 7 Sheets-Sheet 5 KEW/IIA I N V EN TOR.

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Aug. 25, 1953 B. wELTE 2,649,662

BRoAcH SHARPENING MACHINE l filed Nov. 1949 v sheets-sheet e Aug. 25, 1953 Filed NOV. 5, 1949 B, WELTE BROACH SHARPENING MACHINE 7 Sheets-Sheet 7 Patented Aug. 25, 1953 ICE Y, 2,649,662 RoAcH sHAnPENlNG MACHINE Benedict Welle, Lake orion, Mich., assignor to Colonial Broach Company, Warren Township, Mich., a corporation of Delaware `Application November 5, 1949, Serial No. 125,705

2 Claims. (Cl. 51-50) The present invention relates to improved broach sharpening machines. Y

It is an object of the invention to provide an improved universal broach sharpening machine adapted for the sharpening offboth roundand surface broaches, including separate handles, one

for feeding the grindinglwheel in thev sliarpeny ing of round broaches wherein a relatively slight movement of the grinding -wheel transversely of the broach is required, and another for feeding the grinding wheel in the sharpening of surface broaohes wherein a relatively large movement of the grinding wheel transversely ofthe broach is required, and means selectivelyconnecting the handles to render them'foperable for feeding the grinding wheel so that when one ofthe handles is operatively connected for feeding the grinding wheel, the other handle .is disconnected and ineffective. f

Another object ofthe invention is to provide an improved machine for sharpening broaches of the above mentioned typeincluding a removable link means readily connectableto and disconnectable from'each' of 'the handles for readily rendering either of the handles as desired, operatively connected for feeding the grinding' wheel.

It is also an object of this invention to provide an improvedbroach sharpening machine including an adjustable stop mechanism `for limiting the infeeding of the grindingwheel in'sharpening round broaches, and which mechanism may readily be adjusted by the operator from'his normal operating position at the frntof the machine.

A further object of this invention is to provide an improved broach sharpening machine including an adjustable Stop mechanism for limiting the infeeding of the grinding wheel in the sharplening of round broaches, which permits the operator to rapidly feed the grinding wheel toward the broach until the adjustable stop is engaged, thereby speeding up the broach sharpening operation and eliminating the necessity for the voperator infeeding slowly to avoid 'feeding of the grinding wheel beyond' a" desired point.

v Other and more detailed objects' of the invention will become apparent from a consideration of the following specification, the appended claims and the accompanying drawings, wherein:

Figure 1 is a broken perspective4 View of a broach sharpening machine'embodying the present invention, showing .the machine set up for sharpening round broaches,;

Fig. 2 is a broken perspective view of the machine illustrated inFigure 1 showing the machine set up for sharpening surface broaches;

Figure 3 is a broken enlarged'sectional view of the machine illustrated in Figure 1, taken along the line 3 3 thereof; v

Fig. 4 is an enlarged broken plan view of the machine illustrated in Figure l; v

Fig. 5 is an enlarged sectional view ofthe construction illustrated inrFig. 4 ,Htaken along thel Fig. 6 is a broken enlarged sectional view of the construction illustrated in Fig. 4, taken along the line -E thereof;

Fig. 7 is a broken enlarged View of the construction illustrated in Fig. 5, taken along the line l-l thereof;

Fig. 8 is a broken enlarged sectional View of the construction illustrated in Fig. 7, taken along the line 8--8 thereof;

Fig. 9 is an enlarged broken sectional view of the construction illustrated in Figure 1, taken along the line 9 9 thereof;

Fig. 10 is a broken sectional View of the construction illustrated in Fig. 9, taken along the line I-l thereof;

Fig. 11 is an end elevational View of the machine illustrated in Figure 1;

Fig. 12 is a sectional view of the construction illustrated in Fig. 11, taken along the line |2-I2 thereof; and

Fig. 13 is a longitudinal sectional view of a conventional round broach.

Referring to the drawings, and particularly to Figures 1, 3, 4 and 11, the broach sharpening machine there illustrated comprises a main base 2i) having a horizontally movable work slide 22 supported on ways 2l in any suitable manner. The work supporting slide 22 is adapted to support a pair of conventional centers 24 and 26 (see Fig. 1) for rotatably supporting a round broach 28. The center 24 is part of a motor driven head stock mechanism indicated generally at 3U, by means of which the center 24 and the dog 32 may be rotated in order to rotate the broach during the sharpening operation. The motor driven head stock 30 and the tail stock 34 are adjustable along the slide 22 to accommodate broaches of different lengths. The slide 22 may also support a pair of steady rests 36.

The work slide 22 is moved along the ways 2l by a handwheel 23 disposed at the front of the base 2li and secured to a shaft 25 extending into a gear box 2l mounted in the base 20 and housing a suitable reduction gear train generally indicated at 29, including a spur gear 3l operatively engaging a rack 33 mounted on the work slide 22.

When the machine is to be used for sharpenin flat or surface broaches, the table is provided with a suitable chuck such as the magnetic chuck 38 illustrated in Fig. 2.

The machine is'provided at the rear thereof with a vertical slide 40 guided and supported in suitable ways 42 on the base 20, as best shown ingFig. 4. The vertical slide 40 is hollow and is open at its forward face, as best shown in Fig. 3, in order to permit a gear housing 44 which is fixed to the rear wall of the base 20, to project into the slide without interfering with the vertical movements of the slide.

As best shown in Fig. 3, the gear housing 44 rotatably supports a 'worm wheel 46 disposed with its axis extending vertically in bearings 48 and 50 which hold the worm Wheel 4B against 3 axial movement. The housing 44 also rotatably supports a worm 52 with its axis extending horizontally and with the worm in driving engagement with the worm wheel 46. Therworm V5,2 is held against axial movement by bearings -5'4 and 56 (see Fig. 4) and is secured to one end of a horizontally extending shaft :58 which vextends raceway H2 in the plate .|"00 and asimilar cooperating raceway I |4 in a bar I I6 secured with- Y in the slide 98 by screws I I8. The remaining sets forwardly through the front face of the base 20;

The shaft 58 is supported adjacent theV front ,face of the base 20 on a bracket 68 and carries a handwheel 62 fixed to its outer end.

The worm wheel 46 is secured to the upper end of a vertically extending screw V64, the lower end of which has a threaded engagement with an in ternally threaded nut 66 having Van outwardly extending flange at its lower end, upon which the vertical slide 40 is supported by means of .a bearing block 68 keyed to the slide as indicated at 10. It will now be appreciated that the vertical slide 40 may be adjusted upwardly .or .downwardly by rotation of the handwheel 62 Vin the appropriate direction.

The upper wall of the vertically movable slide 40 is formed to denne a hollow cylindrical post 12 and an annular horizontally disposed surface 14 encircling the post 12. This annular surface 14 is engaged by a bearing ring 16 secured to the lower surface of a table 18 which denes a cylindrical bearing 80 in which the post .12 is journaled. A shaft 82 extends vertically through the hollow post 12 and has an annular flange B4 at its upper end which seats on .an annular shoulder 86 vdefined by the table 18 at .the upper end of the bearing 80. At its .lower .end the shaft 82 has a threaded stud portion 88 upon which is received a worn wheel 90 having a threaded central aperture adapted to threadedly engage the stud portion 88. A horizontally disposed worm 92 is rotatably supported in the side wall of the vertically movable slide 40 and is rotatable by a handle 94 disposed externally of the slide 40. Rotation of the handle 94 in one direction rotates the worm wheel 90 in a direction to draw the stud portion 88 and shaft 82 downwardly through the worm wheel 90, upward movement of the wormwheel 90 being prevented by a downwardly extending portion 96 of the post 12. It will .be appreciated that this action results in the shaft 82 acting through the engagement of its flange 84 with the shoulder 86 to clamp the bearing ring 16 against the surface 14 on the vertical slide 40 and lock the table 18 against pivotal movement relative to the slide 40. Rotation of .the handle 94 in the opposite direction releases this clamping action and permits the bearing plate .16 of the table 18 to rotate freely on the annular surface 14 of the slide 40.

A horizontally movable slide 98 is supported on the table 18 for reciprocatory movement relative thereto, and is held against tilting or lateral movement relative thereto as best illustrated vin Fig. 5. The construction there illustrated is described in greater detail in the applicants .copending application Serial No. 125,706 filed November 5, 1949, now abandoned. Briefly, it comprises a bearing plate |00 secured to the upper surface of the table 18 by screws |02, and which is engaged along its opposite edges at its upper .and lower sides by sets of antifriction elements |04, |06, |08, and H0. The upper antifriction elements |04 and |06 carry the -weight of the slide 98 and the lower ones |08 and I|0 co-operate with them to prevent tilting of the slide 98. One set of the upper antifriction elements, namely |04, are balls and co-operate with a. V-shaped Vof antifriction elements |06, |08 and ||0 are cylindrical rollers which roll along raceways on the plate .|00 and .coeoperating raceways on the .members |20, 422 .and |24 secured to the slide 98 1by .screws |26, |28 rand |30 respectively. The individual balls and cylindrical rollers of the sets |04, 106, |00 and |40 are supported in spaced relation along the slide 98 by cages |29, |3|, |32 and |33.

Movement of the slide 98 to the rear, or to the left as viewed in Fig. 3 is limited by the engagement of a stop |35 lcarried by the slide 98 and adjustable along a T-slot |31, best illustrated at the right 'hand side of the slide 98 as viewed in Fig. 5, with .a stop |39 fixed in the forward wall of .the housing |66.

.A rotary wheel support |38 is journaled on the forward end of the horizontal slide 98 for rotation with respect to the slide about .a horizontal axis. The wheel support 38 has a rearwardly extending cylindrical projection |40 which is journaled within a cylindrical recess |42 formed inthe forward end `of the slide 98. The wheel support |38 is held vagainst withdrawal from the recess ,|42 and in desired rotative adjustment relative to the slide 98 .by a stud |44 having its inner end lthreaded into a 'tapped opening in a boss on the slide 98 and secured against rotation by a locking nut |46. The stud |44 extends axially through the rcylindrical recess |42 and cylindrical projection |40 and projects outwardly through 'the forward `surface of the wheel support |38 where it receives a threaded cap nut |48. Upon tightening of the .nut |48, the wheel support A|38 is clamped against the outer annular Surface of a dial ring V|55) mounted on the forward end of the slide 98 and surrounding the recess |42.

The wheel support |38 carries an electric motor '|52 having a .shaft |54 operatively connected by pulley means '('not shown) "to a second sha-ft |56 disposed below and extending vparallel to the shaft |54. The shaft |56 extends outwardly at one side of the wheel support |38 and carries a grinding wheel |58 secured thereto for rotation therewith.

Adjacent its forward end and at the right hand side thereof, as viewed in 'Figure 1, the slide 98 carries a handle |60 mounted thereon for pivotal movement about a horizontal axis. In spaced relation below its pivotal mounting |62, and as best illustrated in Fig. 12, the .handle |60 has an aperture |64 for operatively lconnecting the handle |60 for effecting movement of the slide 98 as hereinafter described.

The table 18 carries ahousing |66 having a horizontally disposed cylindrical socket |68, best illustrated in Fig. .5, which extends parallel to the ,aperture 64 in the downwardly extending end of the pivotally mounted handle |60. A thumb screw |10 is mounted on the housing |66 and has a shank portion extending tangentially into the socket |68 .for a. purpose hereinafter described. A .second handle |12 (see Fig. 2,) is pivotally connected at its upper v.end to a bracket |14 secured to .and extending upwardly from the forward portion of the table 18 at the .opposite side of the slide 98 from the handle |620. The handle |12 is provided with an aperture (not shown) disposed in spaced relation below its upper end for operatively .connecting the handle for effecting movement of the slide 98 relative to the table 18. The $1.14@ 98 has a socket member |16 secured thereto which has a horizontally disposed socket (not shown) similar to socket |68 formed in housing |66 and extending parallel to the aperture in the handle |12. The socket member |16 also has a thumb screw |18 having a shank portion extending tangentially into the socket thereof.

A link |88 is provided for selectively connecting the handle |50 to the housing |66 and the handle |12 to the socket member |16. The link |80 has a bifurcated fitting |82 at its forward end which carries a thumb screw |84 (see Fig. l2) having a shank portion |86 adapted to be inserted through an opening in one of the arms of the fitting |82 and be journaled in the apertures provided in the handles |60 and |12. At its inner end the screw |84 has a threaded stud portion adapted to threadedly engage in a tapped opening in the other arm of the bifurcated fitting |82. The link |80 also carries a cylinder |88 (see Fig. adapted to be rotatably received in the socket |68 and the similar socket of the socket member |16. The cylinder |88 has an annular groove |90 disposed in spaced relation to its inner end and adapted to receive the Shanks of the thumb screws and |18 to permit rotation of the cylinder |88 relative to either the housing |66 or the socket member |16 while preventing axial movement of the cylinder |88. Adjacent its outer end, the cylinder |88 has a transversely extending opening |82 through which the link |80 extends. The cylinder |88 also carries a shoe |94 having a surface shaped to t the link |80, and a thumb screw |96 mounted in the outer end of the cylinder |88 for forcing the shoe |94 against the link |80 to clamp the cylinder against movement relative to the link |80.

It will now be appreciated that the link |80 may be readily moved from the position illustrated in full lines in Fig. 4 to the position there illustrated in broken lines by removing the thumb screw |10 permitting the cylinder |88 to be withdrawn from the housing |66 and removing the thumb screw |84 from the tting |82 to disconnect that fitting from the handle |60. The tting |82 may then be connected to the handle |12 by means of the thumb screw |84 and the thumb screw |96 may be loosened to permit the cylinder |88 to be moved along the link |80 into alignment with the socket member |16 at which point the thumb screw |86 may be again tightened and the thumb screw |18 withdrawn to permit the cylinder |88 to be slipped into the socket of the socket member |16 after which the thumb screw |18 may be replaced to prevent withdrawal of the cylinder |88 from the socket member |18.

The slide 98 also carries a second stop 200 adjustable along the T slot |31 and disposed rearwardly of the stop |35, or to the right thereof as viewed in Figure ll. The stop 200 is secured in the position illustrated in broken lines adjacent the rear of the slide 98 when the link |80 is in the position illustrated in broken lines in Fig. 4 to render the handle |12 operative as when the machine is set up for sharpening surface broaches. When the machine is set up for sharpening round broaches and the handle |60 is rendered operative by the link |80, the stop 200 is xed in approximately the position illustrated in full lines in Figures 4 and l1, forward movement of the slide 98 in response to the operation of the lever |60 is limited by the engagement of the stop 280 with an adjustable stop 282 mounted in the housing |66 secured to the table 18.

Referring particularly to Figs. 'l and 8, the stop 202 is cylindrical in shape and is mounted in a rearwardly extending cylindrical portion 204 of the housing |66 for axial movement between the retracted position there illustrated in full lines and the extended position illustrated in broken lines in Fig. '7. The stop 202 is held against rotation relative to the cylindrical housing portion 204 by a key 206. The extended and retracted positions of the stop 202 are determined by a set screw 206 projecting into a slot 208 formed in the side of the stop 202 and engaging the stop 202 at the opposite ends of the slot 208 when the stop 202 is at its extended and retracted positions. Axial movement of the stop 282 is effected by means of a stud 2 I0 mounted in the housing |66 for rotation about a horizontal axis and held against axial movement by bearings 2 l2 and 2 I4. A rearwardly extending end portion 2|6 of the stud 2|0 has a threaded engagement with the stop 202. Rotation of the stud 2 |0 is effected by means of a spiral gear 2|8 secured on the forward end of the stud 2 |0 in driving engagement therewith. The spiral gear 2|0 is drivingly engaged by a co-operating spiral gear 220 which is secured on the upper end of and driven by a vertically disposed shaft 222 which is rotatably supported in the housing |66 and secured against axial movement by bearings 224 and 226. The shaft 222 is fixed to one end of a flexible cable 228 by means of a set screw 230, the other end of the exible cable 228 being secured to a second vertically disposed shaft 232 which is rotatably mounted and held against axial movement by bearings 236 and 238 mounted in a housing 234 secured to the rear of the base 20. A bevel gear 240 is fixed on the upper end of the shaft 232 for rotation therewith and is drivingly engaged by a second bevel gear 242 fixed on the rear end of a horizontally extending shaft 244 which extends transversely through the base 20, the rear end projecting into the housing 234 and the forward end projecting into a sleeve 246 to which the shaft 244 is keyed as :at 248. At its forward end the sleeve 246 projects into a gear housing 250 wherein it carries a gear 252 keyed thereto as at 254. The sleeve 246 is rotatably supported in bearings 256 and 258. The gear housing 250 is secured to the base 20 by a plurality of screws 260, see Fig. l, and rotatably supports an intermediate gear 262 meshing with the gear 252, and an upper gear 264 meshing with the intermediate gear 262. A pin 266 extends radially through the upper gear 264 to x the same on a shaft 268 extending horizontally through the cover plate 210 on the front face of the gear housing 250 and carries a handwheel 212 xed on its outer end by means of a transversely extending pin 218. The handwheel 212 carries an annular dial 216 secured to the hub portion of the handwheel by a set screw 214 seating in an annular groove 280.

It will now be appreciated that rotation of the handwheel 212 is effective through the shaft 268, the gears 264, 262, and 252, the sleeve 246, the shaft 244, the bevel gears 242 and 240, the shaft 232, the flexible shaft 228, the spiral gears 220 and 2|3, and the stud 2|0, to adjust the stop cylinder 202 along its horizontal axis.

An example of one manner of using the above described adjustable stop mechanism in the sharpening of round broaches is as follows. The broach is mounted in the centers as shown in Figure l. The cap nut |48 is then loosened to permit rotation of the wheel support |38 to a position in which the axis of the grinding wheel spindle |56 lies in a horizontal plane. The handwheel 62 is then rotated to adjust the vertical 23e/regata slide 40 to the position. in which. the grinding Wheel |58 is on the' same. horizontal level as the axis ofthe broach. The handle 94: is then turned to release. the table 'I8 which is rotated until the plane of the grinding Wheel corresponds to the angle made by the face of the broach teeth and it is then clamped in that position by manipulation of the handlev 94.

The sharpening operation may then be carried out in diiering Ways, one of which may include starting. at the end of the broach Where the root diameter is a maximum and adjusting the stop 202 by means of the. handwheel 212 so that when the grinding Wheel |58 is. fed forwardly to the limit permitted by the engagement of the stop 209 with the adjustable stop 202 the infeeding of the grinding Wheel is stopped at the desired point. It Will now be appreciated that in grinding successive teeth of the broach, the root diameters of which are progressively smaller; the grinding Wheel may be fed inwardly until the stop 299 engages the stop 202 Without fear of excessive infeeding of the grinding Wheel and that the additional infeed required in each instance because of the reduction in the root diameter may be readily permitted by a slight adjustment of the handwheel 272. It Will now be appreciated that the broach sharpening machine is arranged so that during such broach sharpening operation the operator may conveniently feed the grinding Wheel` transversely of the: broach byr means of the handle |69 with his left hand and may adjust the position of the Work slide 22 along the base 2.0 by means of the handle 23l with his. right hand, which right hand may also alternately be used for adjustment of the stop 202 by means of the handwheel 212.

The machine is set up for the. sharpening of surface broaches by moving the connecting link |80 to the position illustratedv in full. lines in Fig. 2 and in broken lines. in Fig. 4, in Which position it renders the handle |12 effective for feeding the slide transversely of the broach which is supported as illustrated in Fig. 2. The stop 209 is Ialso moved. along the T slot |37 from the position illustrated in full lines in. Figs. 4 and 1l to the position there illustrated in broken lines. The handle 94 is turned to release the table 'i8 which is then rotated to a position in which the path of movement of the horizontal slide is parallel to the broach teeth, and the table T8 is then clamped in this position by turning the handle 94. The nut |48 isv then loosened and the Wheel support head |33 is rotated to a position such as that illustrated in Fig. 2 in which the plane of the grinding Wheel |53 lies in the plane of the front faces of the broach teeth. The handwheel 62 is then turned to adjust the vertical slide 49 to the position in which the grinding wheel |58 is at the proper height to grind to the rootof the teeth.

While only one embodiment of the invention has been illustrated and described in detail, it Will be readily appreciated by those skilled in the art that numerous modifications and changes may be made Without departing from the spirit of the invention.

What is claimed is:

1. In a machine for sharpening broaches, a base, a horizontally movable slide mounted on said base, means on said slide for supporting and rotating a broach to be sharpened, means including a manually operable element disposed at onev side of said base forl eecting horizontal movement of saidl slide, a table member supported on said base remote from said one side thereof and rotatable about a'. vertical: axis, a horizontally' movable slide member mounted on said table member, a grinding Wheell mounted on said slide member, means for' moving said slide member horizontally; a stop securedv to said slide member, adjustable stopv means mounted on said table member remoteA from said one side of said base and including a stop element adapted to abut said'v stop on said slide member to limit horizontal movement of said slide member in one direction, :and remote control' means for adjusting said adjustable stop means and including a manually operablev element mounted. on one side of said base adjacent said iirst named element, means interconnecting said manually operable element and the said stop element of said adjustable stop means whereby an operator may readily adjust said adjustable stop mea-ns from his normal position at said one side of said base.

2. In a machine for sharpening breaches, a base, a slide mounted on said base for horizontal movement relative thereto, means on said slide for supporting a broach to be sharpened in parallel relation to the lineeof movement of said slide androtating'the broach, means including a handwheel at one. side off said base for eiecting said horizontal movement of said slide, a table member supported on said base remote from said one side thereof, a slide member mounted on said table member, a grinding Wheel, means mounting said grinding Wheel on said slide member for rotation about a substantially horizontal axis, means for rotating saidf grinding Wheel, said table member being rotatable about a vertical axis to align the working surface of the grinding Wheel with the front faces of the broach teeth, said slide member being movable horizontally in one direction relative to said table member to move said grinding Wheel Working surface into the space between adjacent broach teeth, a stop secured to one of said members, adjustable stop means mounted on the other of said members remote from said oneside'of said base and includingI a stop element adapted to abut said stop to limit movement of saidV slide member relative to said table member in said one direction, remote control means including a second handwheel mounted on one side of said base adjacent said first named handwheel and operable for effecting adjustments ofl the stop element of said adjustable stop means, meansincluding a flexible connectoi` interconnectingv said second handvvheel and the said stop element of said adjustable stop means, whereby an operator may readily adjust said adjustablestop means to compensate for variations in the root diameter of the broach from his normal position at said one side of said base, and means adapted to be operated by said operator from said position for moving said slide member in said one direction.

BENEDICT VJELTE.

References Cited' in the le of this patent UNITED STATES PATENTS Number Namel Date 1,660,890 Schramm Feb. 28, 1928 1,840,231. Harrison et al. Jan. 5, 1932 1,862,215 Gallimore June 7, 1932 2,113,287 Baldenhofer Apr. 5, 1938 2,164,212 Le Blond June 27, 1939 2,305,390 Rickenmann Dec. 15, 1942 2,388,785.' Gotberg Nov. 13, 1945 

